/*
 * Copyright (c) JForum Team
 * All rights reserved.
 * 
 * Redistribution and use in source and binary forms, 
 * with or without modification, are permitted provided 
 * that the following conditions are met:
 * 
 * 1) Redistributions of source code must retain the above 
 * copyright notice, this list of conditions and the 
 * following  disclaimer.
 * 2)  Redistributions in binary form must reproduce the 
 * above copyright notice, this list of conditions and 
 * the following disclaimer in the documentation and/or 
 * other materials provided with the distribution.
 * 3) Neither the name of "Rafael Steil" nor 
 * the names of its contributors may be used to endorse 
 * or promote products derived from this software without 
 * specific prior written permission.
 * 
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT 
 * HOLDERS AND CONTRIBUTORS "AS IS" AND ANY 
 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, 
 * BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF 
 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR 
 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL 
 * THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE 
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 
 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES 
 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, 
 * OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER 
 * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER 
 * IN CONTRACT, STRICT LIABILITY, OR TORT 
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN 
 * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF 
 * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE
 * 
 * This file creation date: Mar 29, 2003 / 1:15:50 AM
 * The JForum Project
 * http://www.jforum.net
 */
package net.jforum.util;

import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;

import net.jforum.exceptions.ForumException;

/**
 * Encodes a string using MD5 hashing 
 * 
 * @author Rafael Steil
 * @version $Id: MD5.java,v 1.7 2006/08/23 02:13:44 rafaelsteil Exp $
 */
public class MD5 
{
	/**
	 * Encodes a string
	 * 
	 * @param str String to encode
	 * @return Encoded String
	 * @throws NoSuchAlgorithmException
	 */
	public static String crypt(String str)
	{
		if (str == null || str.length() == 0) {
			throw new IllegalArgumentException("String to encript cannot be null or zero length");
		}
		
		StringBuffer hexString = new StringBuffer();
		
		try {
			MessageDigest md = MessageDigest.getInstance("MD5");
			md.update(str.getBytes());
			byte[] hash = md.digest();
			
			for (int i = 0; i < hash.length; i++) {
				if ((0xff & hash[i]) < 0x10) {
					hexString.append("0" + Integer.toHexString((0xFF & hash[i])));
				}				
				else {
					hexString.append(Integer.toHexString(0xFF & hash[i]));
				}				
			}
		}
		catch (NoSuchAlgorithmException e) {
			throw new ForumException("" + e);
		}
		
		return hexString.toString();
	}
}
